Really sorry to hear that
@LostMyIoniq
Are you absolutely certain that your keyfob(s) do actually go to sleep / stop transmitting. If they don’t then there is always the possibility this was targeted relay theft.
If the keys do go silent then, cloning keys is generally not something trivial or simple to accomplish without physically having the keys.
The other possibility is that there was an exploit on your actual account / Bluelink functionality. If that’s the case then Hyundai won’t be shouting about it from the rooftops and they will be quietly patching things. Though it could constitute a far more serious fleetwide risk. This is how Tesla got caught out a few years ago. Luckily David Colombo was a white hat kind guy instead of a serial car thief entrepreneur